Geobacter sulfurreducens contains separate C- and A-adding tRNA nucleotidyltransferases and a poly(A) polymerase.
The genome of Geobacter sulfurreducens contains three genes whose sequences are quite similar to sequences encoding known members of an RNA nucleotidyltransferase superfamily that includes tRNA nucleotidyltransferases and poly(A) polymerases. Reverse transcription-PCR using G. sulfurreducens total RNA demonstrated that the genes encoding these three proteins are transcribed. These genes, encoding proteins designated NTSFI, NTSFII, and NTSFIII, were cloned and overexpressed in Escherichia coli. The corresponding enzymes were purified and assayed biochemically, resulting in identification of NTSFI as a poly(A) polymerase, NTSFII as a C-adding tRNA nucleotidyltransferase, and NTSFIII as an A-adding tRNA nucleotidyltransferase. Analysis of G. sulfurreducens rRNAs and mRNAs revealed the presence of heteropolymeric RNA 3' tails. This is the first characterization of a bacterial system that expresses separate C- and A-adding tRNA nucleotidyltransferases and a poly(A) polymerase.
Bralley
Patricia
P
Department of Biology, Emory University, Atlanta, GA 30319, USA.
Cozad
Madeline
M
Jones
George H
GH
D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D001483:Base Sequence; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics; D016680:Genome, Bacterial; D045302:Geobacter / Q000145:classification / Q000201:enzymology* / Q000235:genetics; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D010802:Phylogeny; D011061:Poly A / Q000235:genetics; D011062:Polynucleotide Adenylyltransferase / Q000235:genetics / Q000378:metabolism*; D012316:RNA Nucleotidyltransferases / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D018076:DNA, Complementary; D011061:Poly A; D012316:RNA Nucleotidyltransferases; C023198:tRNA nucleotidyltransferase; D011062:Polynucleotide Adenylyltransferase